Peters



2 Sheets-Shet l.

W. M. THOMAS. ELECTRIC ARC LAMP.

(No Model.)

Patented May 22 117551 55d 5 7512 al N. PEYERS. PlwwLnlm mynur. Wnhinglan, uc.

, 2 m e h s b w m 2 s A M O H T M W (No Model.)

ELECTRIC ARC LAMP.

Patented May 22 N. PETERS Phulc-Lwhogmphun \Vashmglnn. ac,

UNITED- j STATES PATENT OFFICE.

WILLIAM M. THOMAS, OF CINCINNATI, OHIO, ASSIGNOR OF ONE-HALFTO SAMUEL WV. SKINNEK OF SAME PLACE.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Application filed August 21. 1882.

To all whom it may concern:

Be it known that I, WILLIAM M. THOMAS, of Cincinnati, Hamilton count-y, Ohio, have inventedcertain new and useful Improvements in Electric-Arc Lamps, of which the following is a specification.

My invention relates toimprovements (which tit them for use in series) in those are electric lamps whose arc-interval is automatically regulated by the electromagnetic action of a helix in circuit with the are upon an armature that is mechanically connected with one of the electrodes.

My previous patents, No. 263,246 and No. 263,247, of 22d August, 1882, may be referred to for more specific description of features common to my several patents in this class.

sequently greater arc-interval, than in the others. Such disproportionate increase of arcinterval in one lamp necessarily weakens the current throughout the series,'and thus detracts from the lifting-power of all, but most so from those of the most sluggish movement. The heavier working -.lamps, thus dwindling in illuminative action, cease one byoneto respond to the continually-waning magnetic energy. In strong contrast with and at the expense of this enfeebled action of the weaker lamps the arc of the most susceptible or easiest-working lamp continues to expand until it practically monopolizes the effective activity of the entire circuit. Such unequal action is remedied by the provision of a high-resistance helix, shunting the are through which current is diverted in proportion to the relative resistance of saidhigh=resistance helix and of the arc, the energy of said high-resistance helix always acting in opposition to that of the suction-core. The resistance of said high-resistance helix is so fixed that when the are is of normal length the forces centered on the electrode movement are in equilibrium. The two conditions of abnormal arc-length adjust themselves as follows: (a) When the arc-resistance is below normal, solittle current is diverted through the highresistance helix that its energy is inappreciable andthe suction-core action is unopposed l atent No. 278,293, dated May 22, 1888.

(No model.) I

l in its duty of lengthening the arc. (b) \Vhen the arc-resistance is above normal, the energy of the high-resistance helix is increased sufficiently to overcome that of the suction-core and to reduce the arc to its normal condition. When this adjustment has taken place, the lamp in question resumesits normal resistance.

scribed insures normal current-flow and equal illuminative action throughout the series.

for this purpose the activities of the electromagnetic instrumentalities have, it is believed, been restricted to the retractile or arc-opening motions, the still more important protraetile or arc-closing actions of the electrodes being or 'electromioving influences of the clectro-magnet being for the time being nonexistant and, so to speak, dead. In such devices it has been customary to employ armature membersof considerable weight, which weight it has been part of the duty of the prime helix to overcome, requiring the powerful magnetic action of many layers of wire, with a correspondingly high resistance and severe draft upon the currentsupply. The device hereinafter described not being dependent for its action on gravity, or employing only suflicient ofit toinsure electrode contact when the current is off, a prime helix of comparatively few layers and low reslstance suffices, and any abnormal elongation of the are is self-corrective by the restriction of the'shunt action, under all'circumstances, to its proper functions of shortening the are.

My invention, as to its leading features, is

matieadjustments or self-righting movements are those of the electro-attractive elements themselves, gravity being either dispensed with, or, when used, acting in a subordinate or auxiliary capacity merely. p

In devices of the kind heretofore employed the automatic correction has depended on means whereby the theater of the inductive action of the high-resistance shunt-helix has been the armature itself, and has depended upon setting up in the armature polar tendencies the reverse of those induced by the prime, so as toneutralize or even for the momentreverse the same. In those forms of such shunts in Which the differential wire is wound upon .Each lamp adjusting itself in the manner do In devices heretofore employed or proposed accomplished solely by gravity, the dynamic directed to means whereby the entire auto-- the prime bobbin there is a serious objection l to this so-called differential methodviz., its liability in those extreme fluctuations which it is most important to control to become subject to afa-lse or reverse action, whose effect is not to narrow but to widen the separation of the electrodes, even to the extent of ru 'ituring the arc and extinguishing the lamp. This in such arrangements is liable to occur whenever the shunted current acquires sufficient relative strength to give its helix an inductive potential exceeding that of the prime. In those forms of such shunts in which the differential wire is wound upon the armature, a serious loss of magnetic effect from the reduction of the armature substance, and loss of proximity to the prime excitant, to provide room for the wire, ensues.

In the preferred form of my present invention the inductions ot the prime helix upon the armature (suction-core) are wholly unaffected by the shunt, and the corrections for series are wholly dependent on the attract-ion between the prime and the shunt. -With this object in view the armature and shunt-helix are so attached to one another as to cause them to be attracted in opposite directions by the prime, with reverse effects upon the position of the electrode-mt one instant retractile, at another protractileaccording to the, for the time being, dominant attraction of core or shunt, respectively. In my preferred forms the armature, (whether ferro-magiretic or solcnoid,) the shunt-helix, and the holder of the positive electrode constitute integrally attached parts of a single moving member, and the electrode, sharing in every motion of this member, takes part in all its perturbations, protractile as well as retractile.

In the preferred type of my present invention the prime helix, conveying the current to the arc, although, as heretofore, stationary during normal changes of the arc-interval, is capable of momentary disengagement and shift of position whenever the arc-interval becomes too great for rectification by the ordinary shunt action.

In the accompanying drawings, Figure 1 is a front elevation of the preferred type of my present invention. Fig. 2 is a side elevation, and Fig. 3 is an axial section, of the electrodynamic members. Fig. 4 is the front elevation of a lamp which embodies certain features of my invention. Figs. 5 and 6 are, respectively, side elevations of the prime helix and of the shunt-helix, with its integrally-attached armature, as employed in the form shown in Fig. 4.

In the preferred type of my invention, A, Fig. 1, may represent a slab, plate, or board, preferably of dry wood or other non-conducting material, for attachment and insulation of operative parts. The plate A carries on its upper side two binding-posts, P and N, for the respective attachment of the positive and the negative rheophores. In Fig.1 the plate A is, by means of tube or cage B, shown connected below with another non-conducting plate or collar, 0, which carries a pendant, 1'.) I), that supports at its lower part a negative electrode, E, which may be of carbon, as shown, or (when immobility of the point of light is desired) of refractory metal. The

negative electrode has electrical connection,

by arm I) of pendant I) D and by cage B, with the negative rheophore N.

The preferred type of my invention has extending vertically through and immovably attached to plate A a brass rod, F, which, being coincident with the axis ofthe tube I3, terminates at or about the level of the collar (3. This rod, called the pendant-rod or f pendant-conductor, serves the twofold purpose of a conductor and a means of suspension of the electro-attractivc mechanism. The upper end of the rod F has electrical connection 1) with positive binding-post I.

Embracing the rod F is a hanger, G, which has hinged to its top a pawl or clutch, H, or other suitable fast and loose device, which is, by means of a weighted heel, Ii, or by a spring, held normally at such obliquity as causes it to nip, and, with its attachments, to remain suspended from the rod F. Attached to, butclec trically insulated from hanger G, is a brass bobbin, Let a hcliX,J,of insulated wire,\vhich connects above, through hanger (I, clutch H, and rod F, with positive rheophore, and below by brush K and other members, now to be de scribed, with positive electrode L. The group of members G H I J K stationary during the normal action of the lamp, but drops at. distantly-recurring intervals, as hereinafter-explained. This intermittently-dropping group of members is known in the present specification as the element Y.

The positive electrode is confined in a brass holder, M, of tubular form, whose upper extremity is screwed within the lower extremity of a soft-iron cylinder, 0, that constitutes the armature or suction-core, against which the brush K, before spoken of, impinges. The said suction-core occupies the interior of the prime helix bobbin I, and has screwed into its upper end the non-conducting bobbin Q, of a highresistance helix which shunts the arc, and is so wound as to be attracted by the prime helix in proportion to current-flow in said shuntheliX. The shunt-wire It connects at its re ceiving end by spiral S with hangerG, and at its discharging end by brush T with cage B, which cage connects with negative binding post N. A sleeve, U, of vulcanitc, serves to insulate from pendant-rod F the electrodeholdcr M and armature 0. Attached to the upper end of shunt-bobbin Q, is a. yokefl, that extends upward through orifices gin hanger G, and which unites at its top with tappet V, which in the lamps normal condition is held (by the electro-dynainic force which acts on the suction-core) out of contact with the clutch The yoke V V, shunt-helix R Q, core 0,

electrode-holder M, and positive electrode L, will be seen to be parts of one shifter member,

which'is held suspended at varying heights relative to the prime helix J, according to the predominance of the upward or downward attractive forces resident in the core and the shunt-helix,respectively. This'singleshifting member, which will hereinafter be designated as the element Z, is by these opposing forces held in such relation to the prime helix as that the centers of the perturbations of force of the core and shunt-helix are respectively restricted to the upper and lower halves of the prime helixs field of energy. Except at distantlyrecurringtluctuations, consequent on the separation of the larger masses of cinder (tackheads) from the negative electrode, or from the carbon-shortening effects of protracted lamp action, the member Y, including the prime helix, remains absolutely quiescent, and

hence may be regarded as normally a fixture in relation to theoscillating member Z, of which the electrode forms a part.

The parts are so adjusted that the closing of the circuit operates, through the attraction of the core, to separate the electrodes the proper distance for a normal are. A slight increase of arc-interval beyond the normal increases the current-flow in the shunt-helix, which'is followed by an attracting downward of the shunt-helix, and a consequent dropping of the electrode. On the contrary, a diminution of arc-interval, by diminishing the mutual attract-ion between the prime and shunt helices, lessens the force opposed to the core-suction, and sets the core free to again lift the electrode. Any excessive electrode-lift-such as establishing a very high resistance are-- would be prejudicial to the series current flow, possibly even to the extent of arc-rupture and extinguishing of series-is remedied by the energy imparted to the shunt by theincreased current-flow o 'er it. This energy operates to depress the moving element Z and to shorten the are of the lamp subject to such action. These perturbations, for the most part, proceed without-entailing a sufficient fall of the armature to disengage the clutch H; but when the arc-interval becomes excessive, as must occur in time by the gradual disintegration of the carbon, and sometimes occurs suddenly by the casting off of a cinder, the shunt action prevails sufficiently to bring the head V in contact with the clutch H, so as to momenta rily disengage the same, and to permit the prime helix and all its appendages to drop, with its clutch, again out of reach of the head or tappet V. In falling the prime helix is arrested by clutch H before it gets out of its field of energy over the suction-core O. When the are is too long the attraction between the prime'and shunt helices draws the member Z toward the member Y. Then, if the mechanism does not allow sufficient space for the high-resistance helix R to adjust the arc, the tappet V pushes against the clutch H, and, as soon as the push is strong enough to loosen the-clutch, the .entire mechanism begins to fall down the pendant-rod, with consequent shortening of the are; but this shortening of the are by decreasing current-flow through the high-resistance helix withdraws the opposition of the latter to the energy of the suctioncore, and the member Z is, so to speak, held suspended by the electro-dynamic attraction of the member Y on the suction-core, while said member Y is by force of gravity moving downward. As soon as pressure is taken off clutch H by the motion incidentto said attraction of the suction-core the clutch again takes hold of rod F, and thelamp has adapted itself to a shorter electrode. This action is so instantaneous and so perfect that there is no visible variation in the light given off. Several consequences ensue from the impact of the tappet V with the clutch H of great value and importance-for example, the preponderanee of core-suction incident to the electrodynamic inactivity of the helix 1%, and the momentary check which its contact with the element Y imparts to the oscillating element Z, coact to cushionthe fall of the latter and prevent collision of the electrodes,

while the almost instantaneous relief of the clutch H from the pressure of tappet V" permits prompt resumption of clutch action and ofimmobility of the element Y. The prime helix, with its entire dependent system of electro-dynamic members, having assumed a new position on the pendant-rod, the normal auto- -matic righting movements are resumed and ical oneness and concurrent motion of core,

shunt, and carbon with the consequent direct agency of the electromagnetic forces in every carbon movement.

While possessing certain generic features in common with the lamps described in several of my contemporaneous applications, the abovedescribed typical form of my present invention is specifically,distinguished in several important particulars-for example, the prime helix, while, like said forms, stationary during normal action,is(in company with the entire regulating mechanism) made capable-on the occurrence of extreme carbon separation-of intermittent momentary drop, thus enabling the use of carbons of much greater length than that of the prime helix bobbin by different specific means to those described in said forms.

Some of the above-stated characteristic features of my invention may be employed in various forms of electriclamps. For example, a

prime helix may be employed which is absolutely stationary, as is shown in former pat-' ents of mine. The shunt and core may be-so attached as tohave their potential ccn ters both below that of the prime, the core acting by attraction toward and the shunt by repulsion from the prime; or the shunt may, as in Fi at, have such longitudinal distance from the core as to act by attraction, but in oppositedirection to the core, and, as in this form, the armature may have fast and loose connection with the electrode. The core may consist of a soft-iron armature or magnet, as shown, or of a solenoid. The frame which attaches the shunt-helix to the core may be provided with a rolling or sliding contact, X, with a bated track upon the prime helixs periphery, so as to permit the gradual shifting of the prime hclixs electro-dyi'iamic field,aud to permit the use of carbons of any desired length. Finally, the arc-opening and arc-closing elements may be made to change places relative to the prime helix, and to both act by repulsion instead of attraction, the core in such case occupying the higher position, and the integrally-attached electrode being the more distant one.

Specific features (shown in Figs.4,5,and (i) are reserved for the subjects of one or more separate applications for patent. Parts in said figures of like functions to those of the preceding forms are similarlydesignated. As hereinbcl'ore intimated, this form is introduced to further illustrate certain distinguishing characteristics of my inventionsuch,for example, as a high-resistance shunt attached integrally to and simultaneously shifting with the core such longitudinal distance as that both act by opposing attractions toward the prime helix, without electrically affecting each other. In this modification the plate 0, of vulcanite orother rigid non-conducting material, affords the means of attachment of the following parts, to wit: the positive and negative binding-posts N 1" of the petulant D D,which supports the negative electrode E, and whose leg D constitutes part of the current-channel to the negative binding-post and the frame B, from whose upper part depends the bobbin 1., of brass or other diamagnetic material, grooved longitudinally at its upper part, as att' t", and reduced in diameter at its lower part, as at 1'. Insulated wire from the positive binding-post being conducted to the groove '5, is carried down the same, and being wound spirally in two or more layers upon the part t', so as to constitute the prime helix J, is conducted oft along the groove t", and thence to the brass holder M of the positive electrode L.

A frame, \V, carries at its lower part a tube, 0, of soft iron, which constitutes the suctioncore, and at its upper part takes the form 'ot' a bobbin, w, upon which is woundin any de-- sired number of convolutions a wire, 1t, of higher resistance than the normal arc, and which connects the positive and negative binding-posts in such a manner as to shunt the are.

As in the form shown in Figs. 1, 2, and 3, the core() and the shunt-helix 1% are held by frame W at such relative longitudinal distance as to place the centersot' their activities one always below and the other-always above the field-center of the prime helix J, and out of electrical influence with each other, and the shunthelix It is so wound as when energized by the overflow-current to be attracted downward in opposition to the upward attraction of the core 0.

The electrode-holder M has a stem, M,which, extending upward through the center and being insulated from the tubular members 0 I B, is in the normal condition of the parts upheld by hook 1 and clutch 2. Depression of the frame \V, by the predominating influence of the shunt It, operates to momentarily release the stem and permit the electrode to drop so as to shorten the are.

The expressions integral attachment and rigid attachment used in this specification are intended to mean that the parts referred to are inseparable during lamp action.

I am aware that it is not new to secure antomatic adjustment of the carbons of electricarc lamps by aprovision of two solenoids or electro-maguets, one of which has acoil of low resistance forming a part of the lamp-circuit, while the other has a coil of higher resistance forming apart of a by-pass or overflow-circuit, such a device being described in the French patent'to Lacassagne and Thiers, of 1855, and again in the device of Tochikolefl', issued in 1869, and described in the Semiere Electrique of 1st of May, 1880, and again in Eng lish patent to Frederick von HcFner-Alteneck, December 4,1878, and in United Statcs patcut to the same, of June 31, 1881. I therefore disclaim novelty insuch expedients, broadl y considered.

Vhatever novel subject-matter I have set forth and not claimed or attempted to claim herein, 1 have claimed or attempted to claim in other applications, or have reserved to be claimed in future original applications.

I claim as new and of my invention- 1. In an electric-arc lamp for series use, the combination, with a relatively-stationary helix in the are circuit, of an oscillating member composed of a duplex core interior to said he hit, whose parts are integrally attached to each other and to the carbon-holder, and of which one part is asoft iron or equivalent core proper and the other a shunt-helix of high resistance, whereby the parts of said member respectively operate, the one to retract and the other to protract, said holder with each varying relation of the direct and the shunted currents, substantially as and for the purpose set forth.

2. In an electricarc lamp for series use, whose arc-current traverses a relatively-stationary prime helix, an oscillating member of the following construction, to wit: a carbonholder having integral attachment to a suctioncore, which core is integrally attached to a high-resistance shunt-helix within the prime helix, and at such longitudinal distance from said core as to subject the said oscillating IIO member to independent oppositely-directed attractions and repulsions of said shunt and core,

substantially as and for the purpose set forth.

3. In an electric-arc lamp for series use, the oscillating member consisting of the suctioncore 0, having integral attachment to carbonholder M, and to the magnetically-independent high-resistance shunt R, interior to the relatively-stationary prime helix J in the arccircuit, substantially as and for the purpose set forth.

4. In an electric-arc lamp for series use, having a relatively-fixed helix in the arc-circuit, the oscillating regulator fastened to the positive electrode, and consisting of the following members -all interior to and coaxial with said fixed helix-to wit, a suction-core of said helix and high-resistance shunt, having endwise attachment to said core, substantially as set forth.

'5. In an electric-arc lamp for series use, the combination, with a relatively-fixed helix in the arc-circuit, of the longitudinally-shifting member comprising the described integrallyattached elements -all coaxial with and interior to said helixto wit, the carbon-holder M and suction-core 0, below the potential center of and attracted upward by said helix, and the endwiseeattached high-resistance shunt It,

above said helixs potential center, and whose convolutions and current-flow are such as to subject it to the downward attraction of said helix, in the manner and for the purposes set forth.

6. In an electric-arc lamp for series use, the combination, with the relatively-fixed prime helix J, of the described armature, arranged within said prime helix, and adapted to oscillate freely along said helixs geometric axis, and whose two elements and the carbon-holder are attached endwise to one another, one element being a suction-core, orits described equivalent and the other a magnetically distinct high-resistance shunt, which respectively operate to retract and protract the said holder as the arc and shunted currents respectively prevail, substantially as set forth.

7 In an electric-arclamp for series use, havin g a relatively-fixed helix, J, in the arc-circuit,

the oscillating member Z, interior to said helix,

consisting of the described rigidly and endwiseattached parts-40 wit, upwardly attracted suction-core O, downwardly-attracted highresistance shunt R, and carbon-holder M, the described construction of said member being such that the carbon-feed is wholly due to the concurrent movements of carbon-holder with said shunt, of which it constitutes a projection, as set forth. v

8. In an electric-arc lamp for series use, the combination, with a prime helix in the arc-circuit, of the oscillating member Z, composed of the following rigidly-attached and concurrently-moving members, to wit: suction-core 0, high resistance shunt-helix It within said prime helix, andthe carbon-holder M, substan- A tially as set forth.

9. In an electric-arc lamp for series use, the combination of pendant-conductor I, in communication above with the positive rheophore and below with the arc, with the intermittent ly-dropping member Y, (consisting of hanger (J, clutch H, bobbin I, helix J, in electrical communication with said rod, and the brush Kin eclectrical communication with the carbonholder,) said member Y being constructed, as described, to exercise oppositely-directed attractions upon and being in the described combination with the electro-magnetically suspended oscillating member Z, (consisting of upwardly-attracted core 0, to which are integrally attached the carbon-holder M and the magnetically-insulated high-resistance shunt R,) the whole being combined and adapted to operate substantially as set forth.

10. In an electric-arc lamp for series use, the described organism of bearing-plate A, pendant rod and conductor F, intermittently-dropping member Y, (consisting of prime helix J, in circuit of the arc, and having hanger G and clutch H,) in combination with the oscillating member Z, (consisting of the following integrally-attached and concurrently-shifting members, to wit: electrode-holder M, core 0, shunthelix R, and tappet V,) the whole being combined and adapted .to operate as set forth.

In testimony of which inventionI hereunto set my hand.

WILLIAM M. THOMAS.

Attest:

GEO. II. KNIGHT, J AS. It. Fonnxnn. 

